Wednesday

BAGHDAD, Iraq, Jan. 10 - Insurgents killed the deputy police chief of Baghdad and his son on Monday morning and later detonated an unusually powerful roadside bomb that destroyed a heavily armored American military vehicle, killing two American soldiers and wounding four in the latest of a string of daylight attacks.

The assassination was the second killing of a senior Baghdad official in six days and came less than three weeks before the national elections that the insurgents have vowed to disrupt.

The police official, Brigadier Amer Naief, and his son, also a policeman, were killed by gunmen at about 7:30 a.m. as the two left their home in the Dora neighborhood of southern Baghdad, an Interior Ministry spokesman said. The militant group led by Abu Musab al-Zarqawi claimed responsibility for the killings in an Internet posting.

Mr. Zarqawi's group has also taken responsibility for the assassination last week of the governor of Baghdad Province, Ali al-Haidari, who was killed when gunmen raked his vehicle with bullets after he left his home in the morning.

An hour after the assassination of Brigadier Naief, a suicide bomber killed four policemen and wounded 19 more when he detonated his bomb-laden pickup truck near the walls of a police station in the southern reaches of Baghdad, according to Dr. Khalid Abdul-Wahid, the director of the Zafaraniya Hospital, where the wounded were taken.

For the second time in four days, insurgents used a huge roadside bomb to destroy a Bradley fighting vehicle, one of the American military's most heavily armored troop carriers, as it was patrolling in southwest Baghdad. On Jan. 6, a bomb in northwest Baghdad killed seven soldiers inside a Bradley.
Senior military officials have warned that insurgents have been stringing together larger and larger explosive devices in their efforts to attack American forces. In many cases, American officials say, the explosives have consisted of several large-caliber Russian-made artillery shells strung together and fused to detonate at the same time.

A similar bomb exploded on a roadside in Mosul on Monday, killing three Iraqi National Guard troops.

The mayhem came as Ukraine, a member of the American-led coalition that has occupied Iraq for more than 20 months, signaled its intent to leave this year. Leonid Kuchma, the outgoing president of Ukraine, ordered a pullout over the next six months of his country's more than 1,600 troops stationed in Iraq. The announcement came after a huge blast in southern Iraq on Sunday that killed eight Ukrainian soldiers and one Kazakh.

Initial comments from Ukrainian defense officials on Sunday had blamed the blast, at an ammunition dump about 50 miles southeast of Baghdad, on an accident. But on Monday, the news service Agence France-Presse quoted a top Ukrainian army commander, Vladimir Mojarovsky, as saying during a briefing in Kiev that "the most probable cause of this tragedy was a planned attack."

The expectation had been that Ukrainian troops would leave Iraq soon, and the Ukrainian president-elect, Viktor A. Yushchenko, has promised to make withdrawal a priority. But the announcement on Monday was more specific about a date.

American military commanders in insurgent hotbeds like Ramadi and Mosul have said in interviews that they have seen attackers use increasingly powerful and sophisticated explosive devices against humvees and armored vehicles. The devices have used elaborate timing sequences and, in some cases, specially shaped explosive charges designed to more easily pierce armor plating.

In Mosul, for example, American commanders were stunned early last month when a patrol of Stryker armored vehicles found itself in a mile-long ambush where insurgents had spaced at least 10 artillery shells about 150 to 200 yards apart, detonating them in a measured pattern as troops passed. The armored Strykers suffered little damage, but commanders on the scene said humvees or lesser-armored vehicles would have been far more vulnerable.

In an even bolder attack at the end of the month, insurgents attacked soldiers from the same unit, the First Battalion, 24th Infantry, with a complicated truck bomb designed to defeat barriers the troops had placed in front of an outpost in western Mosul. The truck had extra-large tires and a raised chassis, and was packed with 1,500 pounds of explosives, but the soldiers had recently installed larger barriers. The detonation created a hole 15 feet long, 8 feet wide and 5 feet deep.

In military parlance, that attack used a V.B.I.E.D. - a vehicle-borne improvised explosive device. Other devices are typically hidden behind brush or refuse or inside the carcasses of dead animals.

For many soldiers - especially those who patrol dangerous areas in humvees - both versions have become the most feared tool of the insurgency.

"The V.B.I.E.D. is a vicious weapon," said Maj. Gen. Peter Chiarelli, the commander of the First Cavalry Division in Baghdad.

Describing an I.E.D. attack that happened last week, he said "it affected immediately the lives of about a hundred folks at the scene, and it created an intimidation factor that is very, very hard for us to judge."

At a news briefing, General Chiarelli said his troops discover and disarm or destroy about one I.E.D. in Baghdad for each one an insurgent detonates.

Perhaps the most common explosives, local commanders say, are artillery shells of the sort that were left in abandoned ammunition dumps after the fall of Saddam Hussein. Instead of using just one shell, the commanders say, insurgents are stringing three or four together. They stack them in cars driven by suicide bombers or rig them to explode on a roadside, using a cellphone in the device to detonate the bomb when it is called. Others have used plastic explosives or other high explosives.

"I.E.D.'s are all being built more powerfully," a senior Pentagon official, Brig. Gen. David Rodriguez, said Friday.

In what was partly a campaign appearance, Dr. Allawi said during a visit to a Baghdad police headquarters that 150 "gangsters" had been arrested who were "specialists in kidnappings, looting, forgery and assassinations," according to a pool report by The Associated Press.

At a news conference, he disclosed that one of the captured insurgents was the commander of one of the most dangerous groups, Muhammad's Army. He said the commander, Raad al-Duri, was snatched days after he took over from a predecessor who had also been captured. Both men are providing information about the insurgency, Dr. Allawi said.

photo credits and captions:

Mauricio Lima/Agence France-Presse--Getty Images

A U.S. soldier arrived to help members of the Iraqi military after an attack on Monday in Mosul. That attack and others in Baghdad came less than three weeks before elections that the rebels have vowed to disrupt.

Sabah Arar/Agence France-Presse-Getty Images

The Baghdad deputy police chief's car hit a wall Monday after gunmen killed the deputy and his son.